Roosegaarde presented several of his groundbreaking solutions to environmental problems at the Fortune Global Sustainability Forum in Yunnan, China on Friday. They include kites that generate electricity and the world’s largest air purifiers, just one of which is capable of cleaning the air in a small town. And he hasn’t just imagined them. He has designed and built them in China and other places.

Roosegaarde believe the solutions to climate change start with intelligent design. His conviction that designers can play an important role in creating change gives him a sense of optimism.

“We live in a world where we are more defined by our future than our history,’’ Roosegaarde said.

Considering rising global temperatures, plastics in the oceans, and fires in the Amazon, the future can be a source of fear and anger among many, including Roosegaarde’s students at Tongji University in Shanghai. Filled with despair, he said they want to know what they should do.

“Don’t be afraid, be curious,’’ is his advice. “I don’t believe in utopia, I believe in protopia: designing prototypes for solutions that create a better world and that can be realized. As humans, we learn, we fail, and we evolve. Stop whining and worrying. We need to fix it.” If they say it can’t be done, Roosegaarde says he’s determined to do it.

Architect and designer Bill McDonough, who pioneered the concept of the Circular Economy, shares that attitude, and has hope for the future. “We don’t want to be depressed, because there is a lot of work to do,’’ he told the Fortune forum. Among McDonough’s prolific works are buildings that generate more electricity than they consume and clothing that is completely biodegradable.

In dealing with government and industry leaders in China and other places, Roosegaarde said he can feel their sense of urgency about the looming threats and the need to take action.

“In China, they are searching for a new harmony between nature and economic progress. We can create a new harmony in society where clean water, clean air, and clean energy are valued. I want to be part of that transition,’’ Roosegaarde said.

McDonough feels that others are also searching for the path to a better world. At the Fortune forum, he said he was moved by the goodwill and willingness to engage he experienced from people across various disciplines and from many corners of the world.

“It was magical and beautiful,’’ he said. “And that’s why this will be possible.”

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